Primary finding
Probable cause
The passenger's inadvertent interference with the flight controls.
Investigator assessment
Analysis narrative
The airplane was being used to conduct aerial photography. While in cruise flight at 6500 feet, the airplane yawed left. Application of right rudder was not fully effective, & when released the airplane yawed further left. Aileron control was sufficient to make a forced landing in a field. Examination of the flight control system & the nose wheel steering failed to reveal any anomalies. The pilot stated that he believed that the passenger, who was conducting the photography, had inadvertently interfered with the flight controls.
Source record
Factual narrative
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